Shunt failure clusters: an analysis of multiple, frequent shunt failures.

Abstract

Repeated failure of ventriculoperitoneal shunts (VPSs) is a problem familiar to pediatric neurosurgeons and patients. While there have been many studies to determine what factors are associated with the first shunt failure, studies of subsequent failures are much less common. The purpose of this study was to identify the prevalence and associated risk factors of clustered shunt failures (defined as 3 or more VPS operations within 3 months). The authors reviewed prospectively collected records from all patients who underwent VPS surgery from 2008 to 2017 at their institution and included only those children who had received all of their hydrocephalus care at that institution. Demographics, etiology of hydrocephalus, history of endoscopic third ventriculostomy or temporizing procedure, initial valve type, age at shunt placement, and other factors were analyzed. Logistic regression was used to test for the association of each variable with a history of shunt failure cluster. Of the 465 included children, 28 (6.0%) had experienced at least one cluster of shunt failures. Among time-independent variables, etiology of hydrocephalus (OR 0.27 for non-intraventricular hemorrhage [IVH], nonmyelomeningocele, nonaqueductal stenosis etiology vs IVH, 95% CI 0.11-0.65; p = 0.003), younger gestational age at birth (OR 0.91, 95% CI 0.85-0.97; p = 0.003), history of a temporizing procedure (OR 2.77, 95% CI 1.12-6.85; p = 0.028), and smaller head circumference at time of initial shunt placement (OR 0.91, 95% CI 0.84-0.99; p = 0.044) showed significant association with shunt failure cluster on univariate analysis. None of these variables maintained significance in a multivariate model. Among children with a history of a shunt failure cluster, 21 (75%) had a shunt infection either prior to or during the shunt failure cluster. A comparison of the infecting organism between these children and 62 children with a history of infection but without a shunt failure cluster showed an association of cluster with gram-negative rod species. Six percent of children in this institutional sample had at least one shunt failure cluster. These children accounted for 30% of the total shunt revisions in the sample. Shunt infection is an important factor associated with shunt failure cluster. Children with a history of prematurity and IVH may have a higher risk for failure cluster.